Return a multidimensional array from pointer function in Visual C++

Question

Hello,

I wrote following code to return multidimensional array from pointer function.Input parameter of this function is one dimensional array, output is pointer that point multidimensional array.

 double  **function( array< double>^ data,int width,int height ) 

  {int i;
  //define returning variable that point multidimensional array
  double **R;
 // memory allocation for R
 R=new double *[height];
 for (i=0;i<=height;i++)
 {
 R[i]=new double [width];
 }

  // ....


  return R;
 }


  int main( void ) {
  int M=2;
  int N=10;
  int  i,j;
  // define multimensional array 2x10

  array< array< double >^ >^ input = gcnew array< array< double >^ >(M);

for (j=0;j<input->Length;j++){
input[j]=gcnew array<double>(N);}

// define result1 and result 2 pointers and memory allocate  for these  variables

 double **result1;
 result1 = new double *[N];
 for(i=0;i<=N;i++)
 {result1[i]=new double [M];}

 double **result2;
 result2 = new double *[N];
 for(i=0;i<=N;i++)
 {result2[i]=new double [M];}

 //............


// send first row array of multidimensional array to function

 result1=function(input[0],M,N)

// send second row array of multidimensional array to function

 result2=function(input[1],M,N)

// delete  result1 and result2
for (i=0;i<=N;i++)
{delete R[k];}
delete R;}*/

 return 0;
 }

I built this program succesfully in Visual Studio 2008.When I debug this code,the program computed result1 pinter variable but during computing result2 in the function here:

R=new double *[height];
for (i=0;i<=height;i++)
 {
 R[i]=new double [width];
 }

Visual Studio give this error:

An unhandled exception of type 'System.Runtime.InteropServices.SEHException' occurred in stdeneme.exe Additional information: External component has thrown an exception.

Unfortunately I can't understand this error. How can I overcome of this problem?Could you help me please?

Best Regards..

Answer 1

The <=s are your problem. Valid array indices go from 0 to N-1. Assigning to result1[N] is an access violation - that's the exception it's complaining about.

Answer 2

At a glance I see one error

for (i=0;i<=height;i++)
 {
 R[i]=new double [width];
 }

you have allocated R[height] but the loop goes height+1

you should write the loop

for (i=0; i<height; i++)

Another thing I see is that when you want destroy your matrix you write

delete R[k];

but it should be

delete [] R[k];

Answer 3

Thanks for your help.

I corrected <=height problem and did it < height but the Visual Studio is going on give the same error.In fact,Visual C++ can compute result1.Unfortunately it can't do memory allocation for result2 variable.Do you have a comment about this topic?